Amazon offers its Prime members the Altec Lansing Orbit Portable MP3 Speaker, model no. IM227, for $16.13 with free shipping. (Non-members can spend $25 or more to qualify for free shipping; otherwise, shipping costs $5.58.) That's the lowest total price we could find by $8, although we saw it for $3 less last fall. This speaker is compatible with MP3 players (including the iPod), CD players, and laptops. It offers up to 24 hours of play on three AAA batteries (not included).

Amazon Prime membership is $79 per year; however, Prime is free for college students for six months, and free for parents and caregivers for three months.